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stack commented on HBASE-5494: ------------------------------ Hmm... NVM. First I need to figure out complete set of zk states and operations they trigger. Making a start up here: https://docs.google.com/spreadsheet/ccc?key=0Aoa3E58mCyOfdFFCY3RmMW9ZeEliTndLNGRNWVBCZkE Don't look yet. It has nothing in it yet. > Introduce a zk hosted table-wide read/write lock so only one table operation > at a time > -------------------------------------------------------------------------------------- > > Key: HBASE-5494 > URL: https://issues.apache.org/jira/browse/HBASE-5494 > Project: HBase > Issue Type: Improvement > Reporter: stack > > I saw this facility over in the accumulo code base. > Currently we just try to sort out the mess when splits come in during an > online schema edit; somehow we figure we can figure all possible region > transition combinations and make the right call. > We could try and narrow the number of combinations by taking out a zk table > lock when doing table operations. > For example, on split or merge, we could take a read-only lock meaning the > table can't be disabled while these are running. > We could then take a write only lock if we want to ensure the table doesn't > change while disabling or enabling process is happening. > Shouldn't be too hard to add. -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira